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981.
In this paper, we assess climate change impacts on an intensively managed grassland system at the Swiss Plateau using the
process-based grassland model PROGRASS. Taking the CO2 fertilization into account, we find increasing yield levels (in the range of 10–24%) and sharp increases in production risks
for an illustrative climate change scenario that suggests a marked increase in temperature and decrease in summer rainfall.
Climate change–induced increases in the coefficients of variation of grassland yields are in the range of 21 and 50%. This
finding underpins that additional risk management strategies are needed to cope with climate-change impacts on grassland production.
The outputs from the grassland model are evaluated economically using certainty equivalents, i.e., accounting for mean quasi
rents and production risks. To identify potential risk management strategies under current and future climatic conditions,
we consider adjustments of production intensity and farm-level yield insurance. The impact of climate change on production
intensities is found to be ambiguous: farmers’ will increase intensity under unconstrained production conditions, but will
decrease production intensity in the presence of a cross-compliance scheme. Our results also show that the considered insurance
scheme is a powerful tool to manage climate risks in grassland production under current and future conditions because it can
reduce the coefficients of variation of quasi rents by up to 50%. However, we find that direct payments tend to reduce farmers’
incentives to use such insurance scheme. 相似文献
982.
This paper explores the impact of the frame in which people interpret global warming. In 1999, 637 respondents completed a mail survey in five counties in central Pennsylvania. Half of the sample received questionnaires that framed global warming in terms of the local impacts of mitigation policies, whereas the other half received questionnaires that framed global warming in terms of the national impacts of mitigation policies. The results show a statistically significant but small difference between the local and national frames in the respondents' willingness to support government policies, as well as to take voluntary actions to mitigate climate change. 相似文献
983.
984.
Perfluorooctane sulfonate (PFOS) is a globally distributed persistent organic pollutant that has been found to bioaccumulate and biomagnify in aquatic food webs. Although principally in its linear isomeric configuration, 21–35% of the PFOS manufactured via electrochemical fluorination is produced as a branched structural isomer. PFOS isomer patterns were investigated in multiple tissues of polar bears (Ursus maritimus) from East Greenland. The liver (n = 9), blood (n = 19), brain (n = 16), muscle (n = 5), and adipose (n = 5) were analyzed for linear PFOS (n-PFOS), as well as multiple mono- and di-trifluoromethyl-substituted branched isomers. n-PFOS accounted for 93.0 ± 0.5% of Σ-PFOS isomer concentrations in the liver, whereas the proportion was significantly lower (p < 0.05) in the blood (85.4 ± 0.5%). Branched isomers were quantifiable in the liver and blood, but not in the brain, muscle, or adipose. In both the liver and blood, 6-perfluoromethylheptane sulfonate (P6MHpS) was the dominant branched isomer (2.61 ± 0.10%, and 3.26 ± 0.13% of Σ-PFOS concentrations, respectively). No di-trifluoromethyl-substituted isomers were detectable in any of the tissues analyzed. These tissue-specific isomer patterns suggest isomer-specific pharmacokinetics, perhaps due to differences in protein affinities, and thus differences in protein interactions, as well transport, absorption, and/or metabolism in the body. 相似文献
985.
Robert D. Rowe Lauraine G. Chestnut 《Journal of the Air & Waste Management Association (1995)》2013,63(7):728-734
Physical and economic impacts of 1978 ambient levels of ozone and sulfur dioxide on 33 crops In the San Joaquin Valley are estimated. The field data regression approach Is used and evaluated for estimating yield losses. The effects of alternative air pollution measures and regression functional forms are evaluated. An economic model is employed that accounts for both farm and market responses to yield improvements from reduced air pollution. Economic damages were estimated to exceed $100 million in 1978 with the biggest losers being the producers of cotton and producers and consumers of grapes, a crop that has heretofore been Ignored in agricultural assessments of pollution damage. 相似文献
986.
Sulfate aerosols (SO4) from anthropogenic emissions of sulfur dioxide (SO2) generally have a cooling effect. However, if SO2 emissions fall over time, accounting for sulfate aerosols will increase the predicted warming from greenhouse gases. This
paper integrates the four marker emission scenarios for CO2 and SO4 from the Special Report on Emissions Scenarios (SRES), the UIUC general circulation model (GCM), and a country-specific impact
model (GIM) to calculate the impacts of sulfate aerosols. By 2100, lower SO2 emissions slightly increase warming in the temperate and polar regions causing small damages in the former and small benefits
in the latter. If SO2 emissions are also lower in tropical regions, temperatures will rise causing small damages there as well. However, if SO2 emissions rise in tropical regions, temperatures will fall leading to small benefits.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
987.
988.
Robert Coates 《Disasters》2021,45(1):86-106
Disaster education outcomes are highly dependent on the political context of that education. Based on a rich, in‐depth case study of the creation of community monitors in a landslide and flood‐prone city in southeast Brazil, this paper demonstrates how developmental and political environments add much additional nuance to existing theories of behaviourist and transformative education for disaster preparedness and mitigation. Beyond identifying the benefits of education, it argues that disaster risk reduction outcomes are reliant on governance frameworks that alter over time. The study reveals the political complexity associated with programme implementation and cites the perspectives of a number of participants. Disaster education is shown to be the necessary yet underappreciated twin of the militarised and technical approaches that dominate disaster response in Brazil. Understated, however, is education's situatedness: how it can become an arena of conflict between government and civil actors over matters of state and society in increasingly hazardous urbanisation settings in Latin America. 相似文献
989.
Evaluating long-term urban resilience through an examination of the history of green spaces in Tokyo
Long-term urban resilience requires urban systems with the capacity to respond to change and disturbance and to enhance the conditions for lasting wellbeing. Over the past century Tokyo has demonstrated impressive resilience, especially a capacity to reorganise and rebuild in response to successive major disturbances. Throughout these recoveries, the city-region maintained a focus on re-establishing, improving and maintaining international competitiveness through industrial development. Green spaces in Tokyo provided a flexible, but gradually disappearing resource. Today, to meet the needs of its ageing and minimally expanding population for enhanced wellbeing, Tokyo requires active transition planning covering many intertwined factors, but the adaptive capacity provided by the green space resource is no longer available. The Tokyo case underscores the risk inherent in the depletion of non-renewable resources (in this instance, green space) to secure immediate recovery and accommodate growth and short-term resilience at the expense of long-term resilience. 相似文献
990.
Objectives: In this study, we aimed to determine whether three minimum legal drinking age 21 (MLDA-21) laws—dram shop liability, responsible beverage service (RBS) training, and state control of alcohol sales—have had an impact on underage drinking and driving fatal crashes using annual state-level data, and compared states with strong laws to those with weak laws to examine their effect on beer consumption and fatal crash ratios.Methods: Using the Fatality Analysis Reporting System, we calculated the ratio of drinking to nondrinking drivers under age 21 involved in fatal crashes as our key outcome measure. We used structural equation modeling to evaluate the three MLDA-21 laws. We controlled for covariates known to impact fatal crashes including: 17 additional MLDA-21 laws; administrative license revocation; blood alcohol concentration limits of.08 and.10 for driving; seat belt laws; sobriety checkpoint frequency; unemployment rates; and vehicle miles traveled. Outcome variables, in addition to the fatal crash ratios of drinking to nondrinking drivers under age 21 included state per capita beer consumption.Results: Dram shop liability laws were associated with a 2.4% total effect decrease (direct effects: β =.019, p =.018). Similarly, RBS training laws were associated with a 3.6% total effect decrease (direct effect: β =.048, p =.001) in the ratio of drinking to nondrinking drivers under age 21 involved in fatal crashes. There was a significant relationship between dram shop liability law strength and per capita beer consumption, F (4, 1528) = 24.32, p <.001, partial η2 =.016, showing states with strong dram shop liability laws (Mean (M) = 1.276) averaging significantly lower per capita beer consumption than states with weak laws (M = 1.340).Conclusions: Dram shop liability laws and RBS laws were both associated with significantly reduced per capita beer consumption and fatal crash ratios. In practical terms, this means that dram shop liability laws are currently associated with saving an estimated 64 lives in the 45 jurisdictions that currently have the law. If the remaining 6 states adopted the dram shop law, an additional 9 lives could potentially be saved annually. Similarly, RBS training laws are associated with saving an estimated 83 lives in the 37 jurisdictions that currently have the laws. If the remaining 14 states adopted these RBS training laws, we estimate that an additional 28 lives could potentially be saved. 相似文献